A synthesized pyrimizine compound, MS-818 has been found to promote neurite outgrowth in neuroblastoma cells and potentiate NGF-induced neurite sprouting of rat PC12 cells. It is thus suggested that MS-818 enhances the activity of some neurotrophic factors, and makes same responses at lower concentrations of neurotrophic factors. In this study, we evaluated the effect of MS-818 on the cellular proliferation and morphological change induced by a and bFGF in rat schwannoma cell RN22 and human glioma cell T98G.Materials and methods: Rat schwannoma RN22 cells and human glioma T98G cells were cultured in minmum essential medium with 10% fetal calf serum. These cells were seeded at 1 10 4 cells per well in 24-well plates and incubated 24 h at 37°C. The cells were treated with varying doses of FGF (0.25, 2.5, 25 ng/ml aFGF; 0.025, 0.25, 2.5, 25 ng/ml of bFGF), and/or added 0.1 mM of MS-818. Then, after 48 h, the cells were detached with heparin, cell numbers were quantitated with a Coulter counter. At the same period, for evaluation of the morphological change, immunocytochemistry was performed, using vimentin in RN22 cells and GFAP in T98G cells.Results: RN22 and T98G cells were increased by aFGF with dose-dependent relationship, and slightly increased by 0.1 mM MS-818 itself. By combination with MS-818, cell numbers were increased, but it was not significant. On T98G cells, cellular proliferation was significantly promoted by bFGF with MS-818, compared with the control group. On RN22 cells, morphological change was induced by aFGF and the proportion of these cells was elevated. By adding MS-818, it was moderately increased.Discussion: In this study, it was suggested that MS-818 might slightly enhance the cellular proliferation induced by FGF at some cell lines, and MS-818 itself posseses that activity a little. Morphological change caused by aFGF could be also slightly promoted, but the mechanism of this effect is not yet clear.